Hi to start this off heres four contemporary online Books on steel making and related practices intended for the practical craftsman, I will follow this up with a number of patents detailing the development of Steel armour over a period of some 50 years.....
I'm researching some markings on a section of FT17 armour plate. They closely resemble the Greek letter omega. Have you come across anything like this is your research? It could be a foundry or tempering mark. Any help would be gratefully received.